Sixty-seven people aged between 27 and 85 were arrested for alleged involvement in vice-related activities, gambling and for being suspected members of unlawful societies, among other offences.
The 46 men and 21 women were nabbed in various locations, including Clarke Quay, Orchard Road and Boat Quay, the police said yesterday.
The anti-crime operation ran between Dec 15 and 26.
During this period, enforcement checks were also conducted at public entertainment outlets and massage establishments.
Five massage establishments were found to be operating without a valid licence, while an unlicensed public entertainment outlet was discovered by the authorities in a factory unit.
Thirty-six patrons aged between seven and 66 were found having a private celebration in the factory. All of them will be investigated for non-compliance with safe distancing measures.
Two organisers, aged 50 and 58, are under investigation for providing public entertainment without a valid licence.
"The police will continue to clamp down on criminal activities during the year-end festive period. Those found engaging in such activities will be dealt with in accordance to the law," the authorities said.